The protection rests
on twin pillars: import restrictions and tests of diseased cattle and people
performed at the National Prion Disease Pathology Surveillance Center (see
"On Watch..." in the bibliography). The center
examines tissue from some CJD victims, and to date, no sign of the human
disease associated with mad cow disease has appeared.

The last imports
of British beef occurred in 1989, and only 32 British animals entered
the food chain during the 1980s. By 1990, the United States had prohibited
the entry of live sheep and cattle , and rendered animal protein, from
Britain.

In
1997, a year after the mad cow meltdown in the United Kingdom, the Food
and Drug Administration (FDA) banned the feeding of ruminant offal to
ruminants. Since then, sparked by the recognition that aberrant prions
spread more easily than expected, federal regulators have banned imports
of beef and byproducts from all of Europe and, just recently, Brazil,
which imported British cows in the 1980s.

Still
worried?
Even a scare about BSE would spell disaster for the beef industry. (Want
The Why Files guide to mad cow lingo?) Skeptics point to these reasons for worrying about the
food supply:

Low
concentrations of disease prions cannot be detected in the laboratory,
so it's not possible to say that a certain food is not contaminated.
Furthermore, the accepted test, made by Prionics
and used on heavily infected animal parts, may miss some cases, according
to a Jan. 11 Reuters
report.

TSEs
have a long incubation period, so disease can crop up years after exposure.
That means control measures take years to work, and errors take years
to surface.

Regulations
may be flouted. A Food and Drug Administration report in January, 2001,
found that "hundreds of feed manufacturers and rendering companies were
not complying with regulations intended to ensure the safety of domestically
produced food," the New York Times reported (see "Stringent Steps..."
in the bibliography).

Some
British renderers (who dispose of diseased cattle) continued to ship
meat and bone meal around the world, and European producers used the
cheap meal at least until November, 2000. Maura Ricketts, a World Health
Organization official, told the New York Times that "The murky movement
of live cattle and rendered animals around the world" had allowed the
cattle disease to spread around the world.

Bovine
by-products are still being imported under loopholes in federal regulations.
Permitted beef products include glandular material from cattle used
for health supplements, and milk, blood, fat, gelatin, tallow, bone
mineral extracts, collagen, semen. The materials are used for vaccines,
medical products and other purposes. The
FDA recently found that some manufacturers were ignoring guidelines
intended to ensure that raw materials for vaccines came from BSE-free
locations. The FDA's Center for Biologics Evaluation and Research says
the chances of vaccine transmission are "remote," but still worth evaluation.

Still, with no
sign that mad cow is present to date, and fairly stiff regulations in
place, the beef industry says the biggest fear is fear itself. Rick McCarty,
an issues manager with the National
Cattlemen's Beef Association, says, "What alarms the industry is misunderstanding
of the disease in this country, seeing everything that's going on in Europe,
and thinking the same thing could happen here."